1. Field of the Invention
This invention relates to a reading lens system, and more particularly to a reading lens system for projecting information such as figures, characters and the like on an original onto a CCD or a line sensor on an enlarged or reduced scale in facsimiles, raster input scanners or the like.
2. Description of the Prior Art
There have been developed various finite conjugate lens systems for use in optical devices.
There has been a demand for finite conjugate lens systems consisting of two lens elements in order to reduce the size and cost of the overall optical devices. For example, a finite conjugate lens system consisting of two lens elements is disclosed in Japanese Unexamined Patent Publication No. 1(1989)-274109. However the lens system disclosed in the patent publication is large in distortion and a projected image is distorted especially in the peripheral portion thereof. Accordingly, the lens system is difficult to use as a reading lens, for instance, in a facsimile.